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Epistemology is the philosophical study of knowledge, including its nature, origins, and limitations. To this end, it attempts to define and distinguish the notions of knowledge, truth and belief.
Epistemology as it pertains to religious belief deals mainly with the standards or criteria for justified religious belief. Key concepts include justification and warrant. Arguments for the justification of religious belief involve either internalism or externalism. The internalist criterion for justification states that we must have cognitive access to the grounds of any belief we hold. Externalism, on the other hand, does not require this access, but requires that one simply have some grounds for one's beliefs.